NO- you can't put a load from a little case with a 45 gr bullet into a bigger case with a 45 gr bullet... it will cause a undercharged load to spike pressures higher than it is supposed to. I know it sounds dumb- less powder more pressure but it is a fact.
Go to the hodgdon site and look up a load for your bullet. And if you get no recipe there read about trail boss, it has lower pressure and is considered quite safe as long as you keep the case 70 - 100% full (Now 100% full does not mean to the top of the case! it means to the base of a seated bullet.)
BUT READ ABOUT IT ON THEIR SITE, don't just take my word for it.
Hope you find what you are looking for and have a fun safe time shooting your light loads.
I have shot trail boss in my hornet and my .223 with 55 gr bullets but I am sure you will find info for lighter bullets too.
The lighter bullet is not the problem with your question, the charge needs to be upped to what is listed for a starting .223 Rem. load. And do not load it unless you read it in a manual or a powder MFG. website..... The web has many opinions. And this is just mine
thejanitor